||These files are used in the dark current subtraction for WFC3 UVIS products from the December 2017 anneal until the last delivery just before the June 2018 anneal. They are a redelivery of an updated version of all those darks previously delivered during that time period. The previous versions were using the November 2017 masterdark to replace hot pixel values which, over time, lead to a false offset. This redelivery will correct all the darks from December 2017 until June 2018 to ensure the correct masterdark is used for the different anneals to ensure the dark current is correctly calculated. Delivered by Catherine Martlin for WFC3.
||Standard delivery of ACS WFC superbias, superdark, and sink pixel reference files following the anneal on December 6, 2018. These files will be used to calibrate ACS WFC observations taken between October 27, 2018 and December 6, 2018. These anneal for these reference files contains one more week than the usual cadence following the gyro switch in October 2018. Delivered by Tyler Desjardins for ACS.
||All of these new files are delivered in support of the new COS cenwaves, 1533 and 800. In addition, the background box parameters were adjusted for PSA FUVA modes in order to avoid active regions along the edge of that segment which produced extra counts in the area where the background was being measured. The new parameters place the boxes in a location that is more appropriate for what the background looks like at the location where science data is taken. Delivered by James White for COS.
||The reason is the deliveries of new COS TDSTAB references and TDSTAB rmap.